A Comprehensive Guide to Chrome’s DNS Management Tool

In the vast ecosystem of internet browsing, Google Chrome stands out as a powerful and versatile web browser. Among its numerous features and settings, Chrome offers a specialized tool designed for managing and troubleshooting DNS (Domain Name System) issues. This tool, accessible via chrome://net-internals/dns, is an essential resource for understanding and resolving DNS-related problems that can affect your browsing experience. This guide will explore the functionality of this tool, its key features, and practical use cases to help you make the most of it.

What is DNS and Why is It Important?

Before delving into the specifics of Chrome’s DNS management tool, it’s crucial to grasp the fundamental concept of DNS. DNS serves as the backbone of the internet by translating human-readable domain names, like www.example.com, into IP addresses, which are numerical identifiers that computers use to locate each other on the network. Without DNS, navigating the web would require memorizing complex numerical addresses for every site, which is both impractical and cumbersome.

DNS is a critical component that ensures the smooth functioning of the internet by allowing users to access websites and online services with ease. It acts as a bridge between user-friendly domain names and the underlying numerical addresses required for computer communication.

Accessing Chrome’s DNS Management Tool

To access Chrome’s DNS management tool, you need to enter chrome://net-internals/dns into the browser’s address bar and press Enter. This will open the DNS section of Chrome’s internal network tools. The interface provides various options and features to help users manage and troubleshoot DNS issues.

Key Features of the DNS Management Tool

1. DNS Cache
   • Description: The DNS cache is a temporary storage area where Chrome keeps records of recently resolved domain names and their corresponding IP addresses. This cache helps speed up the browsing experience by reducing the time required to resolve domain names.
   • Functionality: By accessing the DNS cache, users can view a list of domain names and their associated IP addresses that Chrome has resolved recently. This feature is useful for diagnosing issues related to outdated or incorrect DNS information.
2. Host Resolver Cache
   • Description: Similar to the DNS cache, the host resolver cache keeps track of resolved hostnames and their IP addresses. This cache is used to quickly resolve domain names without repeatedly querying external DNS servers.
   • Functionality: Users can view detailed information about each entry in the host resolver cache, including expiration times and the source of the DNS information. This helps in understanding how Chrome handles DNS lookups and can be useful for troubleshooting issues related to name resolution.
3. Clear Host Cache
   • Description: This feature allows users to clear the host resolver cache. Clearing the cache removes all stored DNS information, forcing Chrome to re-fetch DNS records from the server.
   • Functionality: This option is particularly useful when dealing with DNS-related issues, such as errors or outdated information. By clearing the cache, users can ensure that Chrome retrieves the most current DNS data, potentially resolving problems caused by stale or incorrect entries.
4. Host Resolver Internal State
   • Description: This section provides detailed statistics and information about Chrome’s host resolution process. It includes data on DNS resolution performance and internal operations.
   • Functionality: Users can gain insights into how Chrome performs DNS lookups and identify any anomalies or performance issues. This detailed information can aid in debugging and optimizing the DNS resolution process.
     

     Firefox Web Browser

     In the Firefox web browser the process is almost similar to Google chrome. Here we will need to alter two variables called network.dnsCacheExpiration and network.dnsCacheExpirationGracePeriod. You can follow the following steps to do the same from your browser.

     Open a new tab In the Firefox browser and enter the address about:config. This will get you to a page like the following.

      

     Click on “I accept the risk!” and you will see the list of variables in Firefox as follows.

      

     On the search bar on that page, search for “network.dnsCacheExpiration”

     It should return with two results namely, network.dnsCacheExpiration and network.dnsCacheExpirationGracePeriod with the values set as 60. We will need to double click on that value and change it to 0.

      

     Now, double-click on the value part where it says 60, and set it to 0.

      

     Once done for both the values, reset those to 60 again.

      

     The value we just have changed stores the TTL (Time To Live or expiration time for DNS records). By changing it to 0 makes it immediately clear out the DNS cache. Once done we reset it back to its default value.

     Note: If you are unable to find these values in your browser you will have to manually create those values with 60 and follow the above steps and you are good to go.

     Conclusion

     Great! You’ve successfully purged the DNS cache on your machine. One thing to note is that DNS changes can take up to 48 hours to fully propagate throughout the internet’s DNS servers. You would need to wait a few hours for these changes to take effect.